[Laszlo-dev] For Review: Change 20080107-dda-C Summary: SWF9: Fix grammar glitches in support for ...rest and optional parameters

[Donald Anderson]

Change 20080107-dda-C by dda at lester.local on 2008-01-07 16:44:28 EST
     in /Users/dda/laszlo/src/svn/openlaszlo/branches/devildog
     for http://svn.openlaszlo.org/openlaszlo/branches/devildog

Summary: SWF9: Fix grammar glitches in support for ...rest and  
optional parameters

New Features:

Bugs Fixed: LPP-5234

Technical Reviewer: ptw (pending)
QA Reviewer: hminsky (pending)
Doc Reviewer: (pending)

Documentation:

Release Notes:

Details:
     Previously, parsing of functions with optional or variable  
parameters had glitches.
     The known problems were that seeing a 'public' (and presumably  
any visibility keyword)
     before function caused a function with optional parameters to  
give an error.
     Also, if the function was the first item in the class (before any  
var) this would cause
     an error.  To fix this, I chose to simplify the grammar.  Before,  
the rules that
     any optional parameters must appear after regular parameters, and  
that the vararg parameter
     must appear last was built into the rules of the grammar.  This  
made the grammar complicated,
     and required extra LOOKAHEAD macros to resolve ambigulities.  Now  
the grammar is simple,
     and the rules for the ordering of kinds of parameters are  
enforced after
     the parsing for each element is complete.  All the strange error  
cases related to this part
     of the grammar now appear resolved.

Tests:
     Tried the two cases reported by Henry: 'public' appearing before  
function with opt args,
     and function with opt args appearing first in a class.

     Tried the test/optargs.lzs case for coverage of legal cases.

     Added some (commented) illegal cases in test/optargs.lzs to test  
coverage for illegal cases.

Files:
M      test/optargs.lzx
M      WEB-INF/lps/server/sc/src/org/openlaszlo/sc/Parser.jjt

Changeset: http://svn.openlaszlo.org/openlaszlo/patches/20080107-dda-C.tar



--

Don Anderson
Java/C/C++, Berkeley DB, systems consultant

voice: 617-547-7881
email: dda at ddanderson.com
www: http://www.ddanderson.com